39645 has 12 divisors (see below), whose sum is σ = 68796. Its totient is φ = 21120.

The previous prime is 39631. The next prime is 39659. The reversal of 39645 is 54693.

39645 = T₈₄ + T₈₅ + ... + T₉₃.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (39631) and next prime (39659).

It can be written as a sum of positive squares in 2 ways, for example, as 10404 + 29241 = 102^2 + 171^2 .

It is not a de Polignac number, because 39645 - 2⁶ = 39581 is a prime.

It is a plaindrome in base 16.

It is a nialpdrome in base 15.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 396 + ... + 485.

It is an arithmetic number, because the mean of its divisors is an integer number (5733).

2³⁹⁶⁴⁵ is an apocalyptic number.

It is an amenable number.

39645 is a deficient number, since it is larger than the sum of its proper divisors (29151).

39645 is a wasteful number, since it uses less digits than its factorization.

39645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 892 (or 889 counting only the distinct ones).

The product of its digits is 3240, while the sum is 27.

The square root of 39645 is about 199.1105220725. The cubic root of 39645 is about 34.0980445670.

It can be divided in two parts, 3964 and 5, that added together give a square (3969 = 63²).

The spelling of 39645 in words is "thirty-nine thousand, six hundred forty-five".